JPH01146152A - Video tape picture recorder - Google Patents

Abstract

PURPOSE:To record a video signal without disturbing synchronism by using a video tape recorded previously with a video signal and recording other video signal in place of the previous video signal in tracking the latter signal. CONSTITUTION:A video tape 22 to be used is as recorded previously with a video signal 10. When a video signal 12 or 14 from a video signal source 20 is recorded on the video tape 22, a recording and reproducing circuit 26 and a servo circuit 42 are controlled by a system control circuit 44 to start recording the video signal 12 or 14 other than and in place of the video signal 10 by tracking the recorded video signal 10. By this method, the recording of a video signal can be carried out with no synchronous disturbance.

Description

[Detailed description of the invention] Momme Madaramori! The present invention relates to videotapes, and more particularly to videotape recording devices.

BACKGROUND ART In conventional videotape recording devices, when recording a series of video signals or cuts representing one scene on a videotape followed by another cut representing a different scene, the so-called "
If you do not perform the "Connecting Shooting" operation, the images will be recorded out of synchronization between cuts.

For example, devices that are capable of splicing video using the helical scan method that is often used in home video tape recording devices, when the previous recording ends, move the videotape back a short distance in the opposite direction and start the next recording. was configured to wait for As a result, when the apparatus is started up for the next recording, it is possible to reliably track the magnetic head to the track where the immediately previous video signal is recorded.

More specifically, in a splicing operation, while a series of video signals of a certain scene are being recorded on a videotape, when a certain position on the tape has been recorded, a trigger switch for splicing, such as recording/playback, is activated. When the button is operated, the recording operation is stopped immediately in response. The video tape runs for a certain length due to its inertia until the tape running drive system completely stops, and therefore, video signals are recorded in this portion in a state where the synchronization is disturbed.

When the system stops, the videotape is fed a predetermined length in the opposite direction, and then again fed a certain length in the forward direction until it stops at a certain position.

At this position, the camera takes a recording pause state, for example, and waits for the next trigger switch operation for continuous shooting.When the trigger switch is operated again, tape running starts. After the capstan in the tape running system rotates, the cylinder of the magnetic head rotates, and a servo lock state is established at a certain position on the tape, the next image starts when the magnetic head reaches the correct end position of the previous recording. Start recording the signal. In this way, the next video signal is properly recorded on the videotape without disturbing the synchronization.

As you will see, the continuous shooting operation is complicated,
It takes a relatively long time after recording of a previous cut is stopped until a subsequent cut can be recorded. Furthermore, realizing the continuous shooting function requires a complicated mechanism.

the purpose The present invention overcomes these drawbacks of the prior art.

It is an object of the present invention to provide a videotape capable of recording video signals with a simple mechanism without disturbing synchronization, and a videotape recording device using the same.

According to the present invention, a video tape on which a video signal has been recorded in advance is used, and another video signal is recorded on the video tape in place of the previous video signal while tracking the video signal. Accordingly, video signals can be recorded without disturbing synchronization. It is more preferable that the video signal prerecorded on the videotape represents a simple image, such as uniform white or black.

According to the present invention, a video tape recording device for recording a video signal on a video tape has a magnetic head, receives a first video signal, and supplies the first video signal to the magnetic head to record it on the video tape. a recording means, a tape running means for sliding the video tape in sliding contact with the magnetic head, an operating means for giving an instruction regarding recording of the first video signal on the video tape, and a recording means and tape running means in response to the operating means. a control means for controlling the recording means, tracking a magnetic head in the recording means, and causing the first video signal to be recorded; a second video signal is recorded on the videotape; the control means includes: When a recording instruction is given from the operating means, the recording means and the tape running means are controlled to run the video tape, and the tracking of the magnetic head is controlled based on the second video signal recorded on the video tape; When the magnetic head is on track, the first video signal is recorded on the video tape instead of the second video signal.

Embodiments of a videotape and a videotape recording apparatus according to the present invention will be described in detail with reference to the accompanying drawings.

As shown in FIG. 1, in this embodiment, a video signal obtained from a video signal source 20 is transmitted along with an audio signal as necessary.
This is a video tape recording device that records on a magnetic tape, that is, a video tape 22 using a helical scan method. The video signal source 20 may be, for example, a television camera, other videotape playback device, video signal receiving device, etc., and its composite video and audio signal output 24 is connected to a recording and playback circuit 28 . The recording/reproducing circuit 26 is
These signals are amplified and modulated and the output 27 is supplied to a magnetic head 28. It also has the function of receiving the composite video signal detected by the magnetic head 28 on the signal line 27, amplifying and demodulating it, and supplying signals such as a synchronization signal to the system control circuit 44 from the connection line 4B. As the modulation method of the recording/reproducing circuit 24, frequency modulation is advantageously applied.

The magnetic head 28 is an electromagnetic transducer that is carried by the head cylinder 30 and records video signals on the video tape 22 and reproduces video signals recorded on the video tape 22. That is, the video signal given from the output 27 of the recording/reproducing circuit 28 is recorded on the videotape 22 using a helical scan method, and the video signal recorded on the videotape 22 is read out and sent from the signal line 27 to the recording/reproducing circuit 28. It has a recording and playback function that can be used to record and play videos.

The head cylinder 30 is mechanically linked to a cylinder motor 32, and is rotated by the motor 32 at a predetermined speed in the direction of arrow R1. In the operating state, the videotape 22 is guided by a tape guide 34 so as to be in sliding contact with the circumferential surface of the cylinder 30 as shown in the figure.1 In the normal recording or playback mode, the videotape 22 is guided by a capstan 3B and a pinch roller 38 in the direction of the arrow R2 shown in the figure. Run to.

The cylinder motor 32 and the capstan motor 40 that drives the capstan 3B are servo-controlled by a servo circuit 42 and configured to rotate stably at predetermined speeds.

The system control circuit 44 is a functional section that is connected to the recording/reproducing circuit 28 and the servo circuit 42 through connection lines 46 and 48, respectively, and controls the operation of the entire apparatus in response to the operation of the operating section 50. This is configured, for example, by a processing system such as a microprocessor. Operation unit 5
0 is a manual operation device that is connected to the system control circuit 44 and allows the operator to give various instructions to the device, such as recording and playback. In this embodiment, the operation unit 50 has a trigger switch 52 that gives a recording instruction, and the trigger switch 52 is a non-lock button whose contacts are closed only while the trigger switch 52 is operated. System control circuit 44 interprets the opening of contact 52 as a recording instruction.

The system control circuit 44 controls the running of the tape 22 and the rotation of the cylinder 30 with respect to the servo circuit 42, and controls the recording of video and audio signals onto the video tape 22 with respect to the recording/reproducing circuit 2G. . The tracking function of the videotape 22 is realized using these control functions.

In this embodiment, the videotape 22 has a tape width of 8++u.
The so-called 8mm videotape of ++ was used to advantage;
In this embodiment, the video tape 22 is recorded in a format conforming to the 8 mm video tape standard, and a video tape 22 on which a video signal 10 as shown in FIG. 3 is previously recorded is used. Preferably, the video signal lO prerecorded on this videotape represents a relatively simple raster image, such as a uniform white, halftone or black image. Those in which the signal IO is recorded are advantageously used. When recording the video signal 12 or 14 from the video signal source 20 onto the videotape 22, the system control circuit 44 controls the recording/reproducing circuit 2B and the servo circuit 42 to track the recorded video signal lO. Recording of another video signal 12 or 14 is started in place of the video signal IO. In other words, recording is performed by an operation similar to that of the insert function, and as a result, video signals can be recorded without synchronization disturbance.

In FIG. 3, two adjacent diagonal lines extending upward to the right indicate one video track, and video signals are recorded on each track at different azimuths between the adjacent tracks.

Regarding azimuthal recording, only two of the tracks 12 are shown, and the other tracks are not shown.

In this embodiment, when the recording/reproducing circuit 26 is in the reproducing state, the recording/reproducing circuit 26 reproduces a synchronization signal obtained by the magnetic head 2 from the video signal 10 recorded on the video tape 22 and supplies it to the system control circuit 2B. The control circuit 26 controls the servo circuit 42 in response to this synchronization signal, thereby performing automatic track detection (ATF) servo.

The recording operation in this embodiment will be explained in detail with reference to the flowchart in FIG. When the recording button or trigger switch 52 on the operation unit 50 is operated to put the device in recording mode, the system control circuit 44 controls the servo circuit 42 to stably operate the cylinder motor 32 and capstan motor 40 at a predetermined speed. Rotate it. As a result, the cylinder 30 carrying the magnetic head 28 rotates at a predetermined speed in the direction of the arrow R1, and the video tape 22 runs in the direction of the arrow R2 while slidingly contacting the circumferential surface of the cylinder 30.

The system control circuit 44 puts the recording/reproducing circuit 26 into recording mode. When a video signal and an audio signal are input from the video signal source 20 to the recording/reproducing circuit 26, they are modulated by the circuit 26, amplified, and supplied to the magnetic head 28. As a result, a video signal is recorded on the videotape 22 in a helical scan method (101), and the video signal 10 previously recorded on the videotape 22 is erased at this time.

While a series of video signals 12 (Fig. 3) of a certain scene are being recorded on the videotape 22, for example, when the recording reaches position A on the tape 22, if the trigger switch 52 is restored (102). In response, the system control circuit 44 controls the recording and reproducing circuit 2B to enter a recording pause state, and stops the recording operation by the circuit 2B (1
03), Next, the system control circuit 44 controls the servo circuit 4
2 to stop the power supply to the capstan motor 40 (104), even after the power supply is stopped.

The video tape 22 travels a certain distance due to the inertia of the tape drive systems 38.3B and 40 until they come to a complete stop, and then stops at, for example, position B. However, since no recording is performed in this part, the video signal 1 previously recorded on the videotape 22 is
0 is stored as is without disturbing synchronization. At this position B, wait for the next operation of the trigger switch 52 (105
), in the pause state, the magnetic head cylinder 30 continues to rotate.

When the trigger switch 52 is operated again, the system control circuit 44 controls the servo circuit 42 to resume running the tape 22 (10B), thereby causing the capstan 3B
rotates, and the tape 22 begins to run. At that time, the system control circuit 44 puts the recording and reproducing circuit 2B into the reproducing mode. When the video tape 22 starts running, the magnetic head 28
starts scanning the portion of the video tape 22 where the video signal 10 is recorded. As a result, the magnetic head 28 begins to detect the signal 10 recorded on the video tape 22, and this signal is inputted from the signal line 27 to the recording/reproducing circuit 2B. The recording/reproducing circuit 28 inputs the signal thus detected to the system control circuit 44.

The system control circuit 44 controls the servo circuit 42 to adjust the rotational phase of the cylinder motor 32. videotape 2
2 reaches a steady value, the signal input from the recording/reproducing circuit 26 includes an appropriate synchronization signal, and the system control circuit 44 starts recording the magnetic head 28 of the video tape 22.
is determined to be on-track. In this way, if tracking is successful at, for example, position C, the system control circuit 44 immediately puts the recording/reproducing circuit 28 into the recording mode. As a result, the next video signal 1 is output from the video signal source 20.
4, and if necessary, the audio signal is sent to the recording/reproducing circuit 2B.
The video signal 14 and the audio signal are supplied to the magnetic head 28 through the magnetic head 28, and recording thereof is started (107).The video signal 14 and the audio signal are recorded on the video tape 22 in place of the prerecorded video signal 10. Therefore, the next video signal 14 is properly recorded on the videotape 22 without disturbing the synchronization. When the tape 22 is played back by the playback device,
There is no servo disconnection in the reproduction system, and recorded images are properly reproduced.

In the conventional device, as shown in Fig. 4, when the trigger switch is turned off at position A to take a recording pause state, no video is produced until the trigger switch is turned on again and the servo lock is established. An area 1G where no signal is recorded is generated. Therefore, when the reproducing device covers this area, the servo of the reproducing system becomes disconnected, causing disturbances in the reproduced image.

Although this embodiment was applied to the 8 mm videotape standard, the present invention is not limited thereto, and may be applied to other types of video tape recording apparatus, such as detecting tracks using tracks of different frequencies. Needless to say, it can be applied effectively.

Effect As described above, according to the present invention, by using a video tape on which a video signal has been recorded in advance and recording other video signals on the video tape while tracking the video signal, a simple method can be achieved without disturbing the synchronization. The mechanism can record video signals.

The invention applies particularly advantageously to helical-scan videotape recording devices, in particular to such recording devices equipped with a video camera.

[Brief explanation of the drawing]

FIG. 1 is a functional block diagram showing the configuration of an embodiment of a video tape recording device according to the present invention, FIG. 2 is a flow diagram showing an example of a recording operation in the system control circuit of the device shown in FIG. 1, and FIG. FIG. 2 is a schematic diagram for explaining recording in an embodiment of the present invention. Figure 4 shows the third diagram for explaining recording in the conventional method.
It is a schematic diagram similar to the figure. Explanation of the symbols 22, . . . Video tape 28, . . . Magnetic head 30, . . Cylinder 2B, . Figure 2

Claims (1)

[Claims] 1. A video tape recording device for recording a video signal on a video tape, the device having a magnetic head, receiving a first video signal and transmitting the first video signal to the magnetic head. a recording means for recording the first video signal on the video tape; a tape running means for sliding the video tape in sliding contact with the magnetic head; and an operation means for giving an instruction regarding recording of the first video signal on the video tape. , control means for controlling the recording means and tape running means in response to the operating means, tracking the magnetic head in the recording means, and causing recording of the first video signal; A second video signal is recorded on the tape, and when receiving a recording instruction from the operating means, the control means controls the recording means and the tape running means to run the video tape, and the control means runs the video tape. tracking of the magnetic head is controlled based on a second video signal recorded on the video tape, and when the magnetic head is on track, the first video signal is recorded on the video tape instead of the second video signal. A videotape recording device featuring: 2. A videotape recording apparatus according to claim 1, wherein the second video signal represents a relatively simple image. 3. In the apparatus according to claim 1, when the control means receives an instruction to stop recording from the operation means, the control means controls the recording means in response to the instruction to stop recording the first video signal. A videotape recording apparatus characterized in that recording is stopped and the tape running means is controlled to stop the running of the videotape. 4. In the apparatus according to claim 1, when the recording means is controlled by the control means in response to the recording instruction, the recording means causes the magnetic head to play back from the video tape being run by the tape running means. A video tape recording apparatus characterized in that the second video signal obtained by the second video signal is applied to the control means, and the control means performs tracking of the magnetic head based on the applied second video signal.